Question about skinning

Hi, so I’ve got animation working “mostly” correctly I belive. The problem is that it doesn’t look quite right for everything. For example if I in maya do a simple animation with a single rotating joint and export it, the baked matrix will have scaling as well. This causes some seriously fucked up results, but after reading the spec I’m thinking this is my own fault.

Am I correct in asserting that I actually need to send at least 2 matrices for every joint to my shader to do the actual skinning? One to take the vertex into joint space, and one to do the skinning?